Stock-Based Compensation - Plan Information (Details) shares in Thousands	12 Months Ended
Dec. 31, 2016 item shares	Jan. 01, 2017 shares
Stock-based compensation
Number of stock plans \| item	4
Shares reserved for future issuance	10,184
Expiration period	10 years
Vesting percentage on first anniversary of grant date	25.00%
Remaining vesting period	3 years
2015 Stock Plan
Stock-based compensation
Shares reserved for future issuance		7,800
Employee Stock Purchase Plan 2015
Stock-based compensation
Shares reserved for future issuance		1,100
Maximum employee contributions as a percentage of earnings under the ESPP	15.00%
Purchase price per share expressed as a percentage of the lower of the stock's fair market value on the offering date or purchase date under the ESPP	85.00%

Maximum employee contributions as a percentage of earnings under the Employee Stock Purchase Plan (the ESPP).

No definition available.

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- Definition

Purchase price per share expressed as a percentage of the lower of the stock's fair market value on the offering date or purchase date under the Employee Stock Purchase Plan (the ESPP).

+ References

No definition available.

+ Details

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- Definition

Represents the remaining vesting period under the stock-based compensation plan, in 'PnYnMnDTnHnMnS' format.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of stock awards vesting on the first anniversary of the date of the grant.

+ References

No definition available.

+ Details

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- Definition

Represents the number of stock-based compensation plans.

+ References

No definition available.

+ Details

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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